Add custom "leave to" field in the employee section for terminated users

Currently, Secfix does not allow setting a future end date for employees, as the termination data is synced from Google Workspace. However, for compliance (e.g., ISO requirements) and operational efficiency, we propose adding a separate "Leave To" date field.

This field would:

1. Allow setting a future termination date directly in Secfix Platform.

2. Sync with the HR platform, which typically has the earliest knowledge of an employee's departure.

3. Bonus: Optionally automate the timely deactivation of the Google Workspace account.

This feature would improve data consistency and streamline offboarding processes while ensuring compliance requirements are met.